Experiments will be done to elucidate the structure of the ribosome of E. coli and to relate that structure to its function in protein synthesis. Neutron scattering methods will be used to map the three dimensional arrangement of proteins in the 30S subunit. The influence of binding of proteins S1 and IF-3 to the 30S subunit on the configuration of both entities will be examined and techniques developed so that the location of these components on the ribosome can also be determined by neutron scattering. The components in the EF-G binding sites will be identified by crosslinking. The influence of factors on ribosome conformation will be investigated using thiol blocking agents to detect associated changes in cysteine reactivity. Attempts will be made to crystallize ribosomal proteins and factors in order to open the way for studies of these structures at the atomic level.